Charles Darwin liked to describe the origin of species as "one long argument," but his extensive treatise in support of biological evolution now seems painfully brief compared to the argument that has followed in its wake. Indeed, never in the history of science has a more prolonged and passionate debate dogged the heels of a theory so thoroughly researched and repeatedly validated. And the end is nowhere in sight. Despite all evidence to the contrary, a large portion of the world's population continues to cling to the belief that human beings are fundamentally different from all other life forms and that our origins are unique. It's a lovely sentiment to be sure, but how is it that so many people continue to be drawn to this thoroughly discredited notion?